Apparatus and methods are provided to remove biopsy specimens from a bone and/or associated bone marrow using a powered drive and an intraosseous (IO) needle set. The powered driver may rotate the IO needle set at an optimum speed to obtain a biopsy sample of bone and/or bone marrow. Apparatus and methods may also be provided for aspiration of bone marrow and/or stem cell transplant procedures. The apparatus may include a powered driver, a coupler assembly, a containment bag or sterile sleeve and various IO needles and IO needle sets with associated hubs and/or hub assemblies. Each IO needle set may include a cannula or catheter and an associated trocar stylet with respective tips operable to penetrate a bone and/or bone marrow with minimum trauma to a patient. Each hub assembly may be used to releasably dispose a respective stylet within an associated generally hollow cannula. Some coupler assemblies and/or hub assemblies may also be used with manual drivers.